The present invention relates to an ink ribbon control apparatus and, more particularly, to an ink ribbon control apparatus for a color printer which uses a ribbon cartridge associated with a multicolor ink ribbon for printing.
Color printers are used considerably, for example, for the output terminal of a computer. A color ink ribbon is laterally divided into a plurality of color bands, which are different colors. One end of the ribbon is bonded to the other end to form an endless loop, and is contained in a ribbon cartridge. The cartridge has an inlet and an outlet for the ribbon so that parts of the loop are bridged between the inlet and the outlet. The cartridge is inserted into the printer so that the bridged portion is disposed between a platen and a printing head. In a color printer of serial dot type, the ink ribbon slides a predetermined length between the inlet and the outlet whenever the head performs printing by means of ink on the ribbon. The cartridge is moved in an upward or downward direction to select the color of the character. In other words, the color band of the desired color is opposed to the head by this movement of the cartridge. The head prints a character by hitting the band with printing wires.
The above-mentioned printer generally sets the cartridge to an initial position in response to an initialize signal upon turning of a power source of the printer to ON or from a signal from a host computer, and then moves the cartridge upward from the initial position to oppose the color band of the color of the character to be printed to the head.
The cartridge being used might sometimes need to be replaced with a new ribbon cartridge because the color of the printed characters has become too light. However, when a cartridge is exchanged in a conventional printer, the new cartridge is set at an installed position in the rest area under the initial position. Depending upon the inserting pressure of the cartridge into the printer this rest position is different at every insertion. In the conventional printer, the printing operation is restarted in this state after the cartridge is exchanged. Thus, the character may not printed by the desired color. For example, after the printing is restarted, the front end of the head might be set at the intermediate between two color bands, and the character is printed with mixed colors in this case.